Essential Oil Stabilisation by Response Surface Methodology (RSM): Nanoemulsion Formulation, Physicochemical, Microbiological, and Sensory Investigations

• Published in: Molecules (Basel, Switzerland) Vol. 27; no. 21; p. 7330
• Main Authors: BenJemaa, Mariem, Rahali, Fatma Zohra, Falleh, Hanen, Beji-Serairi, Raja, Megdiche-Ksouri, Wided, Hamrouni, Ibtissem, Hammami, Majdi, Nehme, Ralph, Pereira, Renato B., Andrés, Sonia, Bouhallab, Said, Pereira, David M., Ceciliani, Fabrizio, Abdennebi-Najar, Latifa, Ksouri, Riadh
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 28.10.2022; MDPI
• Subjects: Analysis; Antibiotics; Antiinfectives and antibacterials; Antimicrobial agents; biological activities; Drug resistance; Encapsulation; Enrichment; essential oil; Essential oils; Food; Food and Nutrition; Independent variables; Investigations; Life Sciences; Methods; Microbiology; Milk; nanoemulsion; Nanoemulsions; Oils & fats; Particle size; physical characterisation; Polydispersity; Polynomials; Regression analysis; Regression coefficients; Response surface methodology; RSM experimental design; sensory analysis; Sensory evaluation; Software; Thyme; Variance analysis; Zeta potential; Germany; RSM experimental design; biological activities; essential oil; nanoemulsion; physical characterisation; sensory analysis
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules27217330

This manuscript aimed to optimise the encapsulation of Thymus capitatus essential oil into nanoemulsion. Response Surface Methodology results were best fitted into polynomial models with regression coefficient values of more than 0.95. The optimal nanoemulsion showed nanometer-sized droplets (380 nm), a polydispersity index less than 0.5, and a suitable Zeta potential (−10.3 mV). Stability results showed that nanoemulsions stored at 4 °C were stable with the lowest d3,2, PolyDispersity Index (PDI), and pH (day 11). Significant ameliorations in the capacity to neutralise DPPH radical after the encapsulation of the antimicrobial efficacy of thyme essential oil were recorded. S. typhimurium growth inhibition generated by nanoencapsulated thyme essential oil was 17 times higher than by bulk essential oil. The sensory analysis highlighted that the encapsulation of thyme essential oil improved enriched milk’s sensory appreciation. Indeed, 20% of the total population attributed a score of 4 and 5 on the scale used for milk enriched with nanoemulsion. In comparison, only 11% attributed the same score to milk enriched with bulk essential oil. The novel nanometric delivery system presents significant interest for agroalimentary industries.